Ron Mowrey teaching emulsion making and coating

[paulr]

I got this in a PDF flier today ...so far there doesn't seem to be anything else about it on the web.

Ron Mowrey to teach Emulsion Making and Coating

Kodak may be moving away from making photographic paper, but
that doesn’t mean you can’t make your own. Especially when you
can learn to make both contact and enlarging paper emulsions from
a man who helped develop emulsions for Kodak during its heyday.
Ron Mowrey is a former engineer for Kodak. While he won’t be giving
away any trade secrets, he will show you how you can make
your own emulsions, and how you can coat your own papers for
both contact printing and enlarging papers.

You will also learn how to make a slow camera speed (ISO ~25) emulsion
and prepare and expose a paper negative. This workshop will
open up your photographic world in directions you never dreamed of.
Ron’s workshop will also include doctoring and doping emulsions
with special chemicals to adjust curve shape, speed and coat ability.
Take this workshop and Ron will show you how to produce a
contact paper similar to Azo, in
grades of 1, 2 and 3, and a grade
1 and 2 enlarging speed paper.
If that isn’t enough, use a new
hand-coating blade similar to
those used in the Research
Labs at Eastman Kodak. This
blade will allow you to create
near production quality hand
coatings up to 8x10" in size. It
will dramatically improve the
coating quality obtainable for
silver halide coatings over
what you can now do using
puddle pushers or paintbrushes.

June 18 - 23

www.photoformulary.com

[Donald Qualls]

Ron's been discussing the lead-in to this on APUG for several months as he worked the kinks out of the coating blade design, ISO 25 orthochromatic emulsion process, etc. Based on the examples he's posted there of test images and such, I believe every word of it; given you can make a slow, blue-sensitive enlarging speed paper using 1830s technology (calotype -- one minute, f/8 daylight exposures in camera), it doesn't surprise me at all that you can do it the way Kodak R&D workers did in the 1990s.

I'm not sure I agree with Ron's assessment that film as we know it will be entirely gone within the next 20 years, but I'd bet there'll be a market for hand-coated silver gelatin prints even if you can still buy enlarging paper in 2025 -- just as there's a market for cyanotype, platinum, albumen, and even salted paper prints.

[Oren Grad]

Ron has posted extensively on APUG under the handle "Photo Engineer". You can get a good sense of what he's been doing, and how he thinks about these things, by browsing the discussions under the "B&W: Film, Paper, Chemistry" topic.

[Dan Jolicoeur]

This is confusing for me; I was under the impression that film was made with curtain coaters, not made with a draw through blade.

A matter of fact I had just built A pilot scale coater for some research done with the paper Surface science foundation, with articles published after the research.

I was told that the emulsions for film where done this same way. By a curtain coater, I am talking about a die with a fine gap that the emulsion is sprayed onto the moving sheet underneath, similar to making chocolate candy.

Does anyone have 1st hand knowledge on how the emulsion in a production plant is actually applied to the substrate for film?

I know it is common practice for lab technicians to use a draw bar method with a simple apparatus, i was just curious to how this is done in large scale production now?
Sorry if I got off topic; I just found it interesting about the blade for I have made a few.

[Donald Qualls]

Dan, as I understand it from Ron's posts on APUG, you're correct -- production film is made with curtain coaters, for the most part (though at least one company makes enlarging paper with a blade coater, I gather, since their write-ups say the coating is done vertically, a position that seems incompatible with a curtain coater). However, test coatings were and probably are done with blades during emulsion development, when what's wanted isn't miles of film, many feet wide, but perhaps 100 feet, 10 inches wide. Cleaning curtain coaters is a bit more involved than cleaning a blade system, and in short runs for emulsion testing, cleaning already takes up more time than actual coating.

[Mark Woods]

In the one manufacturing plant I was in, the liquid film emulsion used the same principle as the drink that is made with different "flavors" and appears "stacked" or stripped. The different layers of the emulsion come together and stream over a blade at a given rate onto the film emulsion. Pretty amazing. BTW, is that what you mean by a blade process, or is it a process where the emulsion is put on a medium and a blade draws it across like a squeegee?

MW

[Dan Jolicoeur]

Mark what you saw would be the curtain coated process. You are correct in your last sentence being the so called blade process.
I would like to see the film being made.
Regards,

[Mark Woods]

Dan,

It was pretty amazing. I was in the control room and the whole process was followed via IR cameras and computers. It was far more cool than any set I've been on. The width of the emulsion was 2 meters I believe and a couple of thousand feet long. I couldn't get my head around the fact that what I was watching was actually working! And I've shot with film for many years and never had a clue how it was put together. I know Kodak has a process to do small runs of film to test them or give them to cameramen to test and give opinions. It's all very impressive, too bad the emphasis (and resources) has shifted to digital media. But that's another rant.

MW